The minimum is ROM with the designation U106 377E7.
I would just read it with a ROM programmer, but the question is whether you have a suitable one.
Another option - I can (I hope) write a program that read two of the three ROMs - under the RT-11. But here the question arises - how to transfer the program to PDP-11, and the read data to a computer, in order to send it to me.
Do you have any thoughts?